Militant Aymen Smiri blew himself up on Tuesday evening after security forces surrounded him in the Tunisian capital's Intilaka neighbourhood.
There were no other casualties, officials confirmed.
"Following a long chase, special forces surrounded the terrorist," the interior ministry said in a statement. "When forces began shooting, he blew himself up with an explosive belt he was wearing."
It's the third such incident within a week, which comes months ahead of an election and at the peak of the tourist season.

Saudi Arabia says shrapnel from intercepted ballistic missile in Asir injures one
Nine injured in Australia as car crashes into crowd north of Sydney
India's 'cockroach' youth party to protest, demand poll chief's resignation
Congo's Ebola outbreak has killed more than 4,000, government data shows
About 400 French schools closed as some student protests turn violent
